These are the ones that are coming right out at you, so this is going to be on a second pi orbital.

它们朝向你们，所以这里有另一个π键。

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And we can simplify this expression as saying negative e squared over 4 pi, epsilon nought r squared. Epsilon nought is a constant, it's something you might see in physics as well.

也会遇到它,在这里，你可以就把它,理解为一个转换系数,我们需要做的。

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